Adsorption of SO2 molecule on doped (8, 0) boron nitride nanotube: A first-principles study

Highlights: • Stable adsorption site for SO₂-X-BNNT (X=Al, Ca, Co, Cu, Ge, Ni or Si) is studied. • The formation energies, magnetic moments, and charge transfers are discussed. • Si is more appropriate dopant for the detection of SO₂ molecule. Adsorptions of SO₂ on Al-, Ca-, Co-, Cu-, Ge-, Ni-, and Si-doped (8, 0) boron nitride nanotube (BNNT) have been studied using first-principles approach based on density functional theory in order to exploit their potential applications as SO₂ gas sensors. The electronic properties of the BNNT-molecule adsorption adducts are strongly dependent on the dopants. The most stable adsorption geometries, adsorption energies, charge transfers, and density of states of these systems are thoroughly discussed. This work reveals that the sensitivity of (8, 0) BNNT based chemical gas sensors for SO₂ can be drastically improved by introducing appropriate dopant. Si is found to be the best choice among all the dopants.